JP2011060798A - Ultraviolet irradiation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ultraviolet irradiation device capable of obtaining a uniform illumination distribution in an irradiation region and improving efficiency of irradiation with ultraviolet rays even when a plurality of LED are installed in a row in a line direction. <P>SOLUTION: The ultraviolet irradiation device includes: the LEDs 2 which are installed in a row in the line direction along an irradiation surface 1 and emit ultraviolet rays; a cylinder lens 3 which is disposed in front of the plurality of LEDs 2 along the line direction and has power only in a direction orthogonal to the line direction; and meniscus lenses 4 which are installed in a row corresponding to each of the plurality of LEDs 2 in a state where their optical axes match optical axes 5 of the respective LEDs 2, and have power in entire peripheral directions of the optical axes to make luminous flux of the ultraviolet rays emitted by the LEDs 2 narrow in angle. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an ultraviolet irradiation device that irradiates an irradiation surface in a line using an LED that emits ultraviolet rays.

  Such an ultraviolet irradiation device is used for curing UV (ultraviolet) curable resins, drying UV adhesives, drying UV inks, and the like.

  As such an ultraviolet irradiation device, one having a plurality of LEDs arranged in a line direction to be illuminated and a cylinder lens disposed along the line direction in front of the LEDs is known. . In such an ultraviolet irradiation device, a cylinder lens having power only in a direction orthogonal to the line direction is used, and a direction orthogonal to the line direction to which the ultraviolet rays emitted from the LEDs are irradiated by the action of the cylinder lens. (See Patent Document 1).

See JP 2009-158274 A

  Such an ultraviolet irradiation device is required to have a uniform illuminance distribution on the irradiated surface. However, in the invention described in Patent Document 1, ultraviolet rays emitted from an LED with a light distribution angle of, for example, about 120 degrees are collected using a cylinder lens having power only in a direction orthogonal to the line direction. Therefore, the illuminance distribution in the line direction has not been considered.

  That is, the cylinder lens does not control the light flux in the line direction for the ultraviolet light emitted from the LED, so the illuminance is high near the center of the line-shaped irradiation area, and the illuminance is near both ends of the irradiation area. There is a problem of being lowered.

  The present invention has been made to solve the above problems, and even when a plurality of LEDs are arranged in a line direction, a uniform illuminance distribution can be obtained in the irradiation region, and the irradiation efficiency of ultraviolet rays can be improved. An object of the present invention is to provide an ultraviolet irradiation device that can be improved.

  The invention according to claim 1 is an ultraviolet irradiation device that irradiates an irradiation surface with ultraviolet rays in a line shape, wherein a plurality of LEDs arranged in the line direction and emitting ultraviolet rays, and the front of the plurality of LEDs Between the plurality of LEDs and the cylinder lens, the optical axis of which is arranged along the line direction and having power only in the direction orthogonal to the line direction. In order to narrow the angle of the luminous flux of the ultraviolet rays emitted from the LEDs by being arranged corresponding to each of the plurality of LEDs in a state of being aligned with the axis and having power in the entire circumferential direction of the optical axis. A meniscus lens is provided.

  The invention according to claim 2 is the light distribution full-angle in the line direction of the ultraviolet ray emitted from one of the plurality of LEDs and passing through the meniscus lens and the cylinder lens in the invention according to claim 1. Is substantially coincident with the optical axis of the LED adjacent to the LED.

  According to a third aspect of the present invention, in the second aspect of the present invention, in the direction orthogonal to the line direction, an ultraviolet beam waist emitted from the plurality of LEDs and passing through the meniscus lens and the cylinder lens. Is substantially coincident with the irradiated surface.

  According to a fourth aspect of the present invention, in the third aspect of the present invention, the plurality of meniscus lenses are integrally molded in a state of being connected via a connecting portion.

  According to the first aspect of the present invention, a plurality of LEDs are arranged in the line direction by the action of a meniscus lens that is arranged corresponding to each LED and narrows the ultraviolet light flux emitted from the LED. Even in this case, it is possible to obtain a uniform illuminance distribution in the irradiation region. In addition, since the distance between each LED and the LED side surface of the meniscus lens can be made substantially constant by the action of the meniscus lens, the luminous flux emitted from each meniscus lens can be distributed almost uniformly. It becomes possible to make the illuminance distribution on the irradiated surface more uniform after passing through the cylinder lens.

  According to the invention described in claim 2, since the edge of the light distribution full-angle in the line direction of the ultraviolet rays coincides with the optical axis of the adjacent LED, a more uniform illuminance distribution can be obtained in the entire area in the line direction of the irradiation surface. Can be obtained.

  According to the third aspect of the invention, since the position of the beam waist of the ultraviolet rays substantially coincides with the irradiation surface, the illuminance on the irradiation surface can be improved.

  According to the invention described in claim 4, since the plurality of meniscus lenses are integrally molded in a state where they are connected via the connecting portion, positioning and mounting of the plurality of meniscus lenses can be easily performed. It becomes possible.

It is a side view of the line direction of the ultraviolet irradiation device concerning this invention. It is a side view of the direction orthogonal to the line direction of the ultraviolet irradiation device concerning this invention. It is explanatory drawing which shows the arrangement | positioning relationship between LED2 and the meniscus lens 4. FIG. It is a graph which shows the illumination intensity distribution on the irradiation surface. It is explanatory drawing of the meniscus lens which concerns on other embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a side view of the ultraviolet irradiation apparatus according to the present invention in the line direction, and FIG. 2 is a side view in a direction orthogonal to the line direction.

  This ultraviolet irradiation device is for irradiating the irradiation surface 1 in a line shape with ultraviolet rays, and a plurality of the irradiation surfaces 1 in the line direction along the irradiation surface 1 (the horizontal direction in FIG. 1 and the direction perpendicular to the paper surface in FIG. 2). (Nine in this embodiment) The LEDs 2 that emit ultraviolet rays arranged in a row, and are arranged along the line direction in front of the plurality of LEDs 2 and perpendicular to the line direction (perpendicular to the paper surface in FIG. 1). 2, between the plurality of LEDs 2 and the cylinder lens 3, the optical axis of which coincides with the optical axis 5 of each LED 2. An axisymmetric menis arranged to correspond to each of the LEDs 2 and to have a narrow angle of the luminous flux of the ultraviolet rays emitted from the LEDs 2 by having power in the entire circumferential direction of the optical axis. And a Surenzu 4.

  FIG. 3 is an explanatory diagram showing the positional relationship between the LED 2 and the meniscus lens 4.

  As shown in FIG. 3, the meniscus lens 4 having one convex surface and one concave surface has a shape such that the distance between the concave surface and the emitting portion of the LED 2 is substantially constant. By doing so, an ultraviolet light beam emitted and distributed at an angle from the LED 2 can be incident on the concave surface of the meniscus lens 4 substantially perpendicularly (from the normal direction of the concave surface). For this reason, as shown in FIG. 3, it is possible to distribute the light distribution of the ultraviolet rays emitted from the LED 2 with a substantially uniform light distribution without substantially losing the uniformity, and the illuminance distribution on the irradiated surface after passing through the cylinder lens 3 can be obtained. It becomes possible to make it more uniform.

  As shown in FIG. 1, the ultraviolet rays emitted from each LED 2 and passed through the meniscus lens 4 and the cylinder lens 3 are arranged such that the edge 6 of the light distribution full-angle is arranged next to the LED 2 on the irradiation surface 1. Are arranged so as to substantially coincide with the optical axis 5. That is, as shown in FIG. 1, the LED 2, the meniscus lens 4, and the cylinder lens 3 are arranged such that the outermost portion 6 of the UV light distribution full-angle is positioned on the optical axis 5 of the LED 2 on the irradiation surface 1. Designed. By adopting such a configuration, the illuminance in the line direction of the irradiation surface is such that the light distributions of the two LEDs overlap each other, so that the light distributions of the adjacent LEDs 2 are overlapped over the entire region and are uniform. Illuminance distribution can be obtained. For this reason, it is possible to obtain a uniform illuminance distribution on the irradiation surface 1, that is, the irradiation region.

  As shown in FIG. 2, in the direction orthogonal to the line direction, the position of the ultraviolet beam waist W emitted from each LED 2 and passed through the meniscus lens 4 and the cylinder lens 3 is substantially the same as the position of the irradiation surface 1. Match. Thus, by setting the focal length of the cylinder lens 3, etc., the ultraviolet rays emitted from the LED 2 can be condensed on the irradiation surface 1, and the illuminance of the irradiation surface is improved by reducing the irradiation area. It becomes possible.

  In this embodiment, a power LED that emits a high-output ultraviolet ray is employed as the LED 2. Such a power LED has a feature that the power (light flux) is large but the light distribution angle is wide. For this reason, as the ultraviolet rays spread, the irradiated surface becomes wider, resulting in a problem that the illuminance is lowered. On the other hand, by adopting the configuration described above, even when a plurality of power LEDs are arranged in the line direction, it is possible to obtain a uniform illuminance distribution in the irradiated area while improving the illuminance on the irradiated surface. It becomes.

  FIG. 4 is a graph showing the illuminance distribution on the irradiation surface 1 by the ultraviolet irradiation device described above. 4A shows the illuminance distribution in the line direction described above, and FIG. 4B shows the illuminance distribution in the direction orthogonal to the line direction. In these drawings, the horizontal axis indicates the position on the irradiation surface, and the vertical axis indicates (radiation) illuminance.

  According to the present invention, with respect to the line direction, ultraviolet light having a substantially uniform distribution distributed from the LED 2 at a wide angle is irradiated by the meniscus lens 4 with a narrow light distribution angle without destroying the uniformity. Leads to plane 1. Then, by adopting a configuration in which the light distribution of the adjacent LEDs 2 is overlapped at that time, and more specifically, the light distribution of the two LEDs 2 is overlapped in the entire region, the illuminance in the line direction is finally obtained. Uniformity and illuminance are improved.

  On the other hand, in the direction perpendicular to the line direction, the meniscus lens 4 obtains the same effect as described above, and the cylinder lens 3 condenses the ultraviolet rays, thereby achieving illuminance uniformity and illuminance improvement. ing.

  Therefore, as shown in this figure, in the line direction, a uniform light distribution is achieved by the individual LEDs 2 and the meniscus lens 4, and after passing through the cylinder lens 3, the light distribution is superimposed from the adjacent LEDs 2 on the irradiated surface. Accordingly, a substantially uniform illuminance distribution can be obtained, and a concentrated illuminance distribution having a strong peak can be obtained in a direction orthogonal to the line direction.

  Next, another embodiment of the present invention will be described. FIG. 5 is an explanatory diagram of a meniscus lens unit according to another embodiment of the present invention.

  This meniscus lens unit has a configuration in which a plurality of meniscus lenses 4 at the same positions as those of the above-described embodiment are connected by a connecting portion 9. This meniscus lens unit is integrally molded with the meniscus lens 4 and the connecting portion 9 being connected.

  By adopting such a configuration, the positioning and mounting of the plurality of meniscus lenses 4 can be easily performed.

1 Irradiation surface 2 LED
3 Cylinder lens 4 Meniscus lens 5 Optical axis 6 Edge of full-angle UV light distribution 9 Connection part W Beam waist

Claims (4)

An ultraviolet irradiation device that irradiates the irradiation surface with ultraviolet rays in a line shape,
A plurality of LEDs arranged in the line direction and emitting ultraviolet rays;
A cylinder lens disposed along the line direction in front of the plurality of LEDs and having power only in a direction orthogonal to the line direction;
Between the plurality of LEDs and the cylinder lens, the optical axis is aligned with the plurality of LEDs in a state in which the optical axis coincides with the optical axis of each LED, and the entire circumferential direction of the optical axis A meniscus lens for narrowing an ultraviolet light flux emitted from the LED,
An ultraviolet irradiation device comprising: In the ultraviolet irradiation device according to claim 1,
The edge of the full-angle light distribution in the line direction of the ultraviolet light emitted from one of the plurality of LEDs and passing through the meniscus lens and the cylinder lens is adjacent to the LED on the irradiation surface. An ultraviolet irradiation device that approximately matches the optical axis. In the ultraviolet irradiation device according to claim 2,
In the direction orthogonal to the line direction, an ultraviolet irradiation device in which a position of an ultraviolet beam waist emitted from the plurality of LEDs and passed through the meniscus lens and the cylinder lens substantially coincides with the irradiation surface. In the ultraviolet irradiation device according to claim 3,
The plurality of meniscus lenses are an ultraviolet irradiation device that is integrally molded in a state of being connected via a connecting portion.

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